1. Technical Field
The present disclosure relates to a surgical apparatus having an elongated shaft for laparoscopic and endoscopic procedures. In particular, the disclosure relates to a surgical apparatus having a roll joint permitting an end effector to rotate relative to a distal portion of the elongated shaft.
2. Background of Related Art
Typically in a laparoscopic, an endoscopic, or other minimally invasive surgical procedure, a small incision or puncture is made in a patient's body. A cannula is then inserted into a body cavity through the incision, which provides a passageway for inserting various surgical devices such as scissors, dissectors, retractors, or similar instruments. To facilitate operability through the cannula, instruments adapted for laparoscopic surgery typically include a relatively narrow shaft supporting an end effector at its distal end and a handle at its proximal end. Arranging the shaft of such an instrument through the cannula allows a surgeon to manipulate the handle from outside the body to cause the end effector to carry out a surgical procedure at a remote internal surgical site. This type of laparoscopic procedure has proven beneficial over traditional open surgery due to reduced trauma, improved healing and other attendant advantages.
A steerable laparoscopic or endoscopic instrument may provide a surgeon with a range of operability suitable for a particular surgical procedure. For example, the instrument may be configured such that the end effector may be aligned with a longitudinal axis of the instrument to facilitate insertion through a cannula, and thereafter, the end effector may be caused to articulate or move off-axis as necessary to appropriately position the end effector to engage tissue. When the end effector of a steerable, articulating instrument comprises a pair of jaw members for grasping tissue, the jaw members may need to be oriented relative to the tissue once properly positioned. Orienting the jaws may involve rotating the jaws about the longitudinal axis. However, this type of rotation may frustrate the positioning of the end effector. A roll joint disposed at a distal end of the elongated shaft may alleviate some of the difficulties and facilitate adjustments to either the position or the orientation of the jaws as the end effector approaches the targeted tissue.
One type of laparoscopic instrument is intended to generate a significant closure force between jaw members to seal small diameter blood vessels, vascular bundles or any two layers of tissue with the application electrosurgical or RF energy. The two layers may be grasped and clamped together by the jaws, and an appropriate amount of electrosurgical energy may be applied through the jaws. In this way, the two layers of tissue may be fused together. Many electrosurgical forceps include a conductor extending through the elongated to provide the end effector with an electrosurgical current. In some instances, the conductor may become entangled or may limit the range of motion achievable by the end effector. To offer a surgeon control of such an instrument a roll joint may be provided to facilitate passage of the electrosurgical current therethrough.